Method and apparatus for delivering fluid droplets onto an open and stationary tray

ABSTRACT

The present invention relates to a method and apparatus for delivering droplets of fluids onto an open tray (15) containing poultry. According to the invention, the apparatus comprises a stationary working surface, a single arm (16) supporting a plurality of fluid dispensing nozzles, a drive unit for driving the translation of said arm (16), said plurality of dispensing nozzles being connected to at least one fluid supply circuit comprising a fluid reservoir and a pumping unit, a control unit configured to control the drive unit of the arm and to define at least one duration T of travel of the arm (16) above said working surface. The travel time T includes a period of gradual acceleration of said arm (16) outside an area of said working surface occupied by said tray and bringing said arm to a first end of said tray (15) along the first direction at a travel velocity V, a period of constant velocity V when the arm (16) moves above said tray (15), and a period of gradual deceleration of said arm (16) when the latter has passed a second end of the tray (15) along the first direction. The control unit is also configured to control each pumping unit and activate each pumping unit only when said arm is above said tray.

TECHNICAL FIELD

The present invention relates to a method for uniformly deliveringdroplets of different fluids onto birds placed in an open, stationarytray.

It also relates to an apparatus for distributing droplets of differentfluids onto a stationary tray for the implementation of this method.

PRIOR ART

In order to meet the ever-increasing demand for foodstuffs, animals fromintensive farming systems have become increasingly important.

Good health of these animals, especially to guarantee adequateproduction, requires preventative measures and, in particular,vaccinations to immunize these animals against various diseases duringthe first days of their life.

For example, in poultry farming, vaccines are typically administered tochicks at one day of age or between one (1) and five (5) days of age.

In order to treat a large number of chicks simultaneously, it is a knownpractice to expose these chicks, arranged on trays, or in baskets,moving on conveyors, to fine droplets of water containing the vaccine tobe administered, these droplets being obtained by spraying. The directcontact of these chicks with the droplet mist ensures their vaccinationvia the oculomotor-nasal route.

It is also known that these trays loaded with chicks are passed, bymeans of conveyors, under nozzles ejecting drops of gel containing avaccine, these drops adhering to the surface being colored, for example,in a color attractive to the chick. Such coloring also makes it possibleto ensure that the product has been properly taken up by a simple visualcheck of the front of the animal's mouth.

The drops of gel that fall on the body of each chick are then pecked byother chicks placed nearby so that each chick receives a sufficientamount of vaccine.

Fixed supports are used to support a set of nozzles to deliver dropletsof a specific fluid to a dedicated treatment area, these supports beingarranged to hang over the conveyors transporting the chick-loaded trays.

Thus, when chicks are intended to receive different treatments, thetrays bearing these chicks are transported by means of conveyors todifferent treatment areas separated from each other.

Therefore, it is noted that facilities for mass vaccination of liveanimals, equipped with such conveyer systems, are comprehensive, andtherefore require extensive space.

Such mass vaccination facilities for live animals are therefore notsuitable for all types of operations, especially for small livestockfarms.

There is therefore a pressing need for mass treatment equipment for liveanimals, the original design of which overcomes the above-mentioneddrawbacks of the prior art.

OBJECT OF THE INVENTION

The present invention aims at overcoming the disadvantages of the priorart by proposing a method and an apparatus for mass treatment of liveanimals, which is simple in its design and in its operating method,reliable, fast and requires a reduced space for its implementation.

Another object of the present invention is such a method and such anapparatus for mass treatment of live animals guaranteeing homogeneoustreatment of each live animal contained on an open tray or in a basket.

Yet another object of the present invention is such a method andapparatus that minimizes the loss of treatment fluids while ensuring auniform and homogeneous distribution of these fluids on an open tray.

Yet another object of the present invention is such a method andapparatus for handling open trays of different sizes.

The present invention is also intended for use in the massadministration of two fluids selected from preventive or therapeuticsubstances such as vaccines, nutritional substances or combinations ofthese elements.

To this end, the invention relates to an apparatus for deliveringdroplets of fluids onto an open tray containing poultry.

According to the invention, this apparatus comprises:

-   -   a fixed work surface for receiving and supporting said tray,    -   a single arm bearing a plurality of fluid dispensing nozzles    -   a drive unit for translating said arm along a first direction of        the tray when the latter is on said working surface, said arm        moving above said tray,    -   said plurality of dispensing nozzles being connected to at least        one fluid supply circuit, each fluid supply circuit comprising a        fluid reservoir for supplying corresponding dispensing nozzles        with said fluid and a pumping unit for pumping the fluid from        the reservoir to said corresponding dispensing nozzles, and    -   a control unit configured to control the arm drive unit and        define at least one travel time T of the arm over said working        surface, said travel time T comprising:        -   a period of progressive acceleration of said arm away from            an area of said working surface occupied by said tray and            bringing said arm to a first end of said tray along said            first direction with a travel velocity V,        -   a period of constant velocity V as said arm moves over said            tray, and        -   a period of progressive deceleration of said arm when the            latter has passed a second end of the tray along the first            direction, and in that            -   said control unit is also configured to control each                pumping unit and activate each pumping unit only when                said arm is over said tray.

Advantageously, it is observed that these progressive, i.e. regular andcontinuous, accelerations/decelerations avoid the occurrence of jerks inthe movement of the arm, which would be likely to cause undesired lossof fluids from the tray.

This minimizes fluid losses, which can be very costly for the operator.

Moreover, this device is compact and can be used with success on smallfarms.

The tray has a rectangular or square section; the first direction isadvantageously the length of this tray and the second direction is thewidth of this tray. Of course, variants are possible.

By “bird” we mean any avian species, such as birds of the Ayes class,i.e. vertebrate animals which are feathered winged, bipedal, endothermic(warm-blooded) and able to lay eggs. In the context of the presentinvention, birds refers more particularly to birds of economic and/oragronomic interest, such as poultry (e.g., chickens, turkeys, hens,guinea fowl, quail, partridges and pigeons), migratory birds (e.g.,ducks and geese) and ornamental birds (e.g., swans, parrots andPsittacidae).

Such an apparatus for distributing droplets of fluids finds applicationsin particular in the field of vaccination of chicks within a few days oftheir birth, i.e. between one (1) and five (5) days of age, preferablyat one (1) day of age, i.e. 24 hours after hatching

According to an embodiment of this apparatus for delivering droplets offluids, it comprises at least one sensor for detecting the area occupiedby said tray on said working surface, said at least one sensor sendingtray positioning signals to said control unit. Preferably this apparatuscomprises one or more object detection devices such as adjustableposition stops or one or more optical devices for determining thedimensions of said tray.

It is thus possible for the control unit to determine the different timeperiods depending on the position on the work surface and/or thedimensions of the tray.

According to another embodiment of this apparatus for delivering fluiddroplets, each pumping unit is an electric, pneumatic or hydraulic pump.

Preferably, it is a syringe pump whose piston is driven by an electric,pneumatic or hydraulic activator.

According to yet another embodiment of this apparatus for deliveringdroplets of fluids, it comprises at least two separate supply circuitseach having a pumping unit, this control unit being a programmable unitfor individually activating/deactivating said or some of said pumpingunits.

It is thus possible not only to manage the activation or not of eachpumping unit according to the fluids to be delivered but it is alsopossible to define for each supply circuit the desired volume of fluidto be delivered.Preferably, this programmable unit is a microcontroller.

According to yet another embodiment of this apparatus for deliveringdroplets of fluids, this drive unit comprises an electric motor whichincludes a gear wheel, this gear wheel meshing with a gear track of aguide rail extending along the first direction of the tray.

Alternatively this drive unit is a linear activator, the mobile armbeing mounted perpendicularly, or substantially perpendicularly, to thefree end of this activator. This linear activator can be an electric,pneumatic or hydraulic activator.

According to yet another embodiment of this apparatus for dispensingdroplets of fluids, this arm carries a first set of dispensing nozzlesfor dispensing at least one first fluid and a second set of dispensingnozzles for dispensing at least one second fluid, distinct from the atleast one first fluid, the dispensing nozzles of each set being arrangedso that the entire dimension of the tray along a second directionperpendicular to the first direction is covered by these first andsecond sets of dispensing nozzles, when this tray is received on thesaid working surface.

Advantageously, this apparatus is configured to provide a time delaybetween the dispensing of at least one first fluid by means of saidfirst set of dispensing nozzles and at least one second fluid by meansof said second set of dispensing nozzles are spaced apart from eachother on said arm along the first direction by a distance defining thistime delay. Advantageously, this distance is calculated to guarantee aneffective treatment of the poultry by the second fluid.

As an example, the spacing between the two (2) assemblies is between 4and 10 cm, preferably between 4 and 7 cm, even more preferably thespacing is 5 cm.

In yet another embodiment of this apparatus for delivering droplets offluids, the first set of nozzles comprises fluid spray nozzles and thesecond set of nozzles comprises fluid spray nozzles or needles forejecting individual drops of a fluid.

While being advantageously compact, this apparatus can deliver in a veryshort time interval, even quasi-simultaneously, two distinct fluids suchas a spray and a gel, to treat in mass poultry placed on a tray or in abasket.The creation of a time lag between the distribution of the two fluidsavoids the dilution of the gel drops by the mist of droplets of thefirst fluid.

The spray nozzles can have flat or conical heads. Preferably, they areflat to form a curtain of droplets.

Each of these nozzles is configured to eject an individual drop of fluidthrough its orifice at a given fluid pressure.

Such a device has applications in the veterinary field, especially forthe mass vaccination of chicks.

The present invention also relates to a method for delivering dropletsof fluids onto an open tray containing poultry, said tray beingstationary.

According to the invention,

-   -   a mobile arm is moved over said working surface, translating        along a first direction of said tray, said arm carrying a        plurality of fluid dispensing nozzles, said dispensing nozzles        being arranged to cover the entire dimension of the tray in a        second direction perpendicular to the first direction,    -   said arm is moved for at least a time T of movement of the arm        over said working surface, said time T of movement including:        -   a period of progressive acceleration of said arm away from            an area of said working surface occupied by said tray and            bringing said arm to a first end of said tray along said            first direction with a movement velocity V,        -   a period of constant velocity V as said arm moves over said            tray, and        -   a period of gradual deceleration of said arm when said arm            has passed a second end of said tray along said first            direction, and            -   said plurality of dispensing nozzles being connected to                at least one fluid supply circuit, each fluid supply                circuit comprising a fluid reservoir for supplying                corresponding dispensing nozzles with said fluid and a                pumping unit for pumping the fluid from the reservoir to                said corresponding dispensing nozzles, said pumping unit                of said at least one fluid supply circuit being                activated only when said arm is moved over said tray.

This time T of the arm's movement only includes these three periods:

acceleration/palliation/deceleration. However, it is possible thatduring the treatment of a same tray, this arm makes a round trip abovethis tray to ensure the treatment of the chicks contained in this onewith two distinct fluids. In fact, this arm is then moved during twotimes T of movement.

According to an embodiment of this method for dispensing droplets offluids, this arm bears a first set of dispensing nozzles and a secondset of dispensing nozzles, said nozzles of each set being arranged tocover the entire dimension of the tray in a second directionperpendicular to the first direction droplets of at least one firstfluid are dispensed simultaneously by means of said first set ofdispensing nozzles and droplets of at least one second fluid, distinctfrom the first fluid, are dispensed simultaneously by means of saidsecond set of dispensing nozzles of two distinct sprays or two distinctgels.

Alternatively, this arm bearing a first set of dispensing nozzles and asecond set of dispensing nozzles, the nozzles of each set being arrangedto cover the entire dimension of the tray in a second directionperpendicular to the first direction, the following steps are performed:

-   -   a) firstly dispensing droplets of at least a first fluid by        spraying through the first set of dispensing nozzles,    -   b) then at least one second fluid, distinct from the at least        one first fluid to be sprayed, is distributed by ejection of        individual drops by means of the second set of distribution        nozzles.

This method allows the administration of at least two different fluidsto chicks contained on an open tray or basket in a very short time,while ensuring a homogeneous treatment of each chick.

The original design of this method requires a reduced space for itsimplementation and it is thus particularly well-adapted toimplementation on small farms.

This mobile arm being advantageously adjustable in height, this methodcan be implemented with any type of open tray. The adjustment in widthis carried out by the withdrawal, the blocking by stopper, or thenon-use of certain nozzles and/or needles for application located on theperiphery of the mobile arm.

Advantageously, such a method is particularly suitable for theadministration of a spray (a first fluid) and a gel (a second fluid).

Preferably, steps a) and b) are performed with a single pass of themobile arm over the tray, these nozzle assemblies being arranged on thisarm so as to generate a time lag between steps a) and b).

Advantageously, the time offset between steps a) and b) is determined toguarantee the effective treatment of the poultry by said at least onesecond fluid.It is thus ensured that each bird is directly exposed to the secondfluid or consumes a sufficient quantity of this second fluid so that themass treatment of the birds is homogeneous.In other words, the time interval between steps a) and b) of fluiddistribution is calculated to avoid the possibility that the dropletmist obtained by distribution of the first fluid by means of the firstset of distribution nozzles may reduce the adhesion, or wetting, of thedroplets of the second fluid ejected by the second set of distributionnozzles, in particular when this latter fluid is a gel.Alternatively, step a) is performed as said arm moves from a first edgeto a second edge of said tray, said second edge being opposite saidfirst edge, on a forward path extending along said first direction andstep b) is performed as said arm moves from said second edge to saidfirst edge on a return path along said first direction.

In yet another embodiment of this method for delivering fluid dropletsonto an open tray, the first fluid is a liquid to be sprayed and thesecond fluid is a gel such as a soft gel, or a fluid having a viscositybetween 50 and 200 cps at 20° C. Preferably, the viscosity of this fluidis between 50 and 180 cps at 20° C. and even more preferably between 54and 177 cps at 20° C. Even more preferably, the viscosity is between 100and 120 cps at 20° C. Purely as an illustration, the first fluid is anaqueous composition containing a vaccine.

This gel may include a coloring agent to visually control the uniformdistribution of the drops on the open tray.

According to yet another embodiment of this method for delivering fluiddroplets onto an open tray, in each of steps a) and b), a plurality ofdroplets having a uniform or substantially uniform size are formed.

This can be accomplished by controlling the fluid supply pressure ateach nozzle of each assembly for a given nozzle type.Preferably, in step a) a mist of droplets is formed, at least 80%,preferably at least 90%, of such droplets having a size between 145microns and 230 microns.Advantageously, in step b) a plurality of droplets is formed, at least80%, preferably at least 90%, of these droplets having a size between900 microns and 1500 microns.

According to yet another embodiment of this method for deliveringdroplets of fluids onto an open tray, the flow rate through said nozzlesand the speed of movement of the moving arm are controlled to ensure auniform or substantially uniform distribution of said droplets over thetray.

Preferably, the flow rate through each of said nozzles, delivering thefirst fluid, being between 6 ml/sec and 40 ml/sec, preferably between 8ml/sec and 20 ml/sec, and the flow rate through each of said needles,delivering the second fluid, being between 15 ml/sec and 50 ml/sec,preferably between 15 ml/sec and 25 ml/sec. The pressure applied todeliver the first fluid is between 3 and 130 bar, and the pressureapplied to deliver the second fluid is between 0.2 and 1 bar.

According to yet another embodiment of this method for deliveringdroplets of fluids onto an open tray, said fluids incorporate one ormore active ingredients for vaccinating poultry species such as birds,or fluids other than vaccines such as nutritional compositions.

According to yet another embodiment of this method for deliveringdroplets of fluids onto an open tray, at least two distinct first fluidsare dispensed by spraying and/or at least two distinct second fluids aredispensed by ejecting individual drops.

For illustrative purposes only, each set of dispensing nozzles maycomprise two nozzle manifolds for dispensing two different products in asingle pass.The present process thus also covers the distribution of two or moredistinct fluids to be sprayed, or atomized, and/or two or more fluids tobe ejected in the form of individual drops. The latter fluids arepreferably ejected through needles.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages, purposes and particular embodiments of the presentinvention will be apparent from the following description, which isprovided, for explanatory purposes and not in any way restrictive, withreference to the accompanying drawings, in which:

FIG. 1 is a front view of an apparatus for mass processing of chicksaccording to a particular embodiment of the present invention;

FIG. 2 is a perspective view of the apparatus in FIG. 1 ;

FIG. 3 is another perspective view of the apparatus of FIG. 1 ;

FIG. 4 is a perspective and top view of the apparatus of FIG. 1 , with abasket containing chicks placed in its working area and awaitingprocessing;

FIG. 5 is a cross-sectional view of the apparatus in FIG. 1 , with abasket containing chicks placed in its working area and awaitingprocessing;

FIG. 6 illustrates the three phases of operation of the motor of themobile arm drive unit, with acceleration, bearing and deceleration;

DESCRIPTION OF AN EMBODIMENT

The following drawings and description contain, for the most part,certain elements. They may therefore not only serve to better understandthe present invention, but also contribute to its definition, ifnecessary.

First of all, we note that the figures are not to scale.

FIGS. 1 to 5 schematically illustrate a chick mass processing apparatusaccording to a particular embodiment of the present invention.

This apparatus comprises a building 10 provided with feet 11 having attheir free end casters 12 to ensure the movement of the latter. Theapparatus can have from 2 to 4 wheels 12. Each of these wheels 12 canhave a locking device (not shown) to fix the apparatus in position.

This building 10 comprises in its upper part an enclosed space borderedby walls 13 which are at least partially transparent to visualize theinterior of this space.

One of these walls 13 comprises a mobile flap 14 in vertical translationto allow access to this closed space, in particular for the introductionand removal of a basket 15 loaded with chicks, also for the cleaning andmaintenance of the apparatus.In addition to this physical barrier constituted by the mobile flap 14,and if it is desirable that the apparatus remain open, this apparatuscan comprise one or more protection elements (not shown) to detect thepresence of an object introduced into the treatment area such as thehand or arm of an operator. This or these protection elements are ableto send detection signals to a central processing unit, which can stopan ongoing process or prevent the process from being started. As anexample, this or these protection elements are infrared detectors.Of course, it is still possible that the building 10 does not have sucha movable flap 14 or such protection elements.

The interior of this enclosed space includes a work area for receivingand supporting an open basket 15 for processing, with the basket 15 in astationary position.

A mobile arm 16, mounted on a longitudinal rail 17 defining a firstdirection, can translate along the rail 17 over the work area. Thelongitudinal rail 17 is attached to the upper end, or cover, of thebuilding 10.

This mobile arm 16 is powered for movement by a drive unit comprising anelectric motor including a gear wheel, said gear wheel meshing with agear path of the longitudinal rail 17 extending along the firstdirection of the basket 15.

This mobile arm 16 bears a set of nozzles 18 and a set of depositneedles 19, these nozzles and these needles being arranged on the mobilearm 16 in such a way that the entire dimension of the basket 15 along asecond direction perpendicular to the first direction defined by thelongitudinal rail 17, is integrally covered by the set of nozzles 18 andby the set of deposit needles 19.

These nozzles and needles can be individually moved along the movablearm 16 to allow adjustment of the coverage of different baskets.

Of course, this device can include position sensors (not shown) todetermine the precise positioning of the basket in the working area. Itis then possible to automate the fluid dispensing sequences by automaticrecognition of the type of basket 15 placed in the dispensing device.

One set of nozzles 18 comprises spray nozzles while the other setcomprises dispensing needles 19, each of which comprises an orifice,each needle being configured to eject an individual drop of fluidthrough its orifice at a given fluid pressure.

While being advantageously compact, this apparatus makes it possible todeliver in a very short time interval, even quasi-simultaneously, twodistinct fluids such as a spray and a gel to treat poultry in massplaced in an open basket.

This device comprises two reservoirs 20 which are placed in a support 21at the height of the user, these reservoirs 20 being advantageouslytransparent to check the available level of fluid in each of them.

Each fluid supply circuit connecting a reservoir 20 to its correspondingnozzle and dispensing needle assembly includes a syringe pump 22 fordrawing fluid from its corresponding reservoir into the supply circuit.Each syringe pump 22 comprises a piston activated by a pneumaticactivator.

This apparatus includes a control unit (not shown) that allows eachsyringe pump 22 to be controlled and activated only when the arm movesover the basket 15.

This control unit is also configured to control the drive unit of thearm and to define a period of time T of movement of the mobile arm 16over the working area comprising

-   -   a period of progressive acceleration of said arm 16 out of the        basket 15 and bringing said arm to a first end of said basket 15        along the first direction with a movement velocity V,    -   a period of constant velocity V as said moving arm 16 moves over        said basket 15, and    -   a period of progressive deceleration of said arm 16 when said        arm 16 has passed a second end of said basket 15 along said        first direction.

Such an embodiment not only guarantees a uniform distribution ofdroplets over the open basket but also ensures that fluid consumption islimited to the volume of fluid needed to treat the chicks. It can beobserved that the fluid losses that could result from irregular movementof the mobile arm 15 are eliminated

The apparatus is therefore economical and space-saving

The nozzle assembly 18 and the dispensing needle assembly 19 are alsoarranged on the mobile arm 16 to provide a time lag between thedispensing of the first fluid (vaporizable fluid) and the second fluid(gel).

This elongated mobile arm comprising two lateral edges that constitute afront and a rear face, considered in the direction of translationalmovement of this arm along the first direction, the nozzle assembly 18is mounted on the front face of this mobile arm 16 while the depositneedle assembly 19 is mounted on the rear face of this mobile arm 16,thus being separated from the nozzle assembly 18 along the firstdirection.

This ensures that the distribution by spraying, or even by atomization,of the droplets of the first fluid by the first nozzle assembly 18always precedes the distribution of the droplets of the second fluid bythe deposit needle assembly 19.

Thus, there is no risk that the droplet mist created by spraying thefirst fluid may prevent the drops of the second fluid from adhering tothe feathers of the chicks, which could lead to an inhomogeneoustreatment of the latter.

According to an embodiment of the present apparatus, the minimumdistance d spatially separating the nozzle assembly 18 from thedispensing needle assembly 19 along the first direction is between 5 and9 cm. The speed of movement of the arm in its uniform range of movementis between 35 and 80 cm/second, preferably 55 cm/second.

1. An apparatus for delivering droplets of fluids onto an open tray (15)containing poultry, characterized in that it comprises: a stationarywork surface for receiving and supporting said tray (15), a single arm(16) bearing a plurality of fluid dispensing nozzles, a drive unit fortranslating this arm (16) along a first direction of the tray (15) whenthe latter is on said working surface, said arm (16) moving above saidtray (15), this plurality of dispensing nozzles being connected to atleast one fluid supply circuit, each fluid supply circuit comprising afluid reservoir for supplying corresponding dispensing nozzles with saidfluid, and a pumping unit for pumping the fluid from the reservoir tosaid corresponding dispensing nozzles, and a control unit configured tocontrol the drive unit of the arm and to define at least one travel timeT of the arm (16) over said working surface, said travel time Tcomprising: a period of progressive acceleration of said arm (16) out ofan area of said working surface occupied by said tray and bringing saidarm to a first end of said tray (15) along the first direction with amoving velocity V, a period of constant velocity V as said arm (16)moves over said tray (15), and a period of progressive deceleration ofsaid arm (16) when said arm has passed a second end of said tray (15)along said first direction, in that said control unit is also configuredto control each pumping unit and activate each pumping unit only whensaid arm is over said tray.
 2. The apparatus according to claim 1,characterized in that it comprises at least one sensor for detecting thearea occupied by said tray on said working surface, said at least onesensor sending tray positioning signals to said control unit.
 3. Theapparatus according to claim 1, characterized in that each pumping unitis a syringe pump.
 4. The apparatus according to claim 1, characterizedin that said drive unit comprises an electric motor having a gear wheel,said gear wheel meshing with a gear track of a guide rail extendingalong the first direction of the tray (15).
 5. The apparatus accordingto claim 1, characterized in that the drive unit is a linear activator,said mobile arm (16) being mounted perpendicularly to the free end ofthis activator.
 6. The apparatus according to claim 1, characterized inthat said arm (16) carries a first set of dispensing nozzles (18) fordispensing at least one first fluid and a second set of dispensingnozzles (19) for dispensing at least one second fluid, distinct from theat least one first fluid, the dispensing nozzles of each set beingarranged so that the entire dimension of the tray (15) along a seconddirection perpendicular to the first direction is covered by these firstand second sets of dispensing nozzles, when this tray (15) is receivedon said working surface.
 7. The apparatus according to claim 6,characterized in that it is configured to provide a time lag betweendispensing at least a first fluid through said first set of dispensingnozzles (18) and at least a second fluid through said second set ofdispensing nozzles (19).
 8. The apparatus according to claim 7,characterized in that said first and second sets of dispensing nozzles(18,19) are spaced apart from each other on said arm (16) along thefirst direction by a distance determining said time lag.
 9. Theapparatus according to claim 6, characterized in that said the first setof nozzles (18) comprises nozzles for spray dispensing of a fluid andsaid second set of nozzles (19) comprises nozzles for spray dispensing afluid or needles for ejecting individual drops of a fluid.
 10. A methodfor delivering droplets of fluids onto an open tray (15) containingpoultry, said tray (15) being stationary and placed on a workingsurface, characterized in that: A mobile arm (16) is moved over saidwork surface, translating in a first direction of said tray (15), saidarm (16) carrying a plurality of fluid dispensing nozzles, saiddispensing nozzles being arranged to cover the entire dimension of thetray (15) in a second direction perpendicular to the first direction,said arm is moved for at least a travel time T of the arm (16) over saidworking surface, said travel time T comprising: a period of progressiveacceleration of said arm (16) out of an area of said working surfaceoccupied by said tray and bringing said arm to a first end of said tray(15) along the first direction with a moving velocity V, a period ofconstant velocity V as the arm (16) moves over said tray (15), and aperiod of progressive deceleration of said arm (16) when said arm haspassed a second end of said tray (15) along said first direction, inthat this plurality of dispensing nozzles being connected to at leastone non-therapeutic fluid supply circuit, each fluid supply circuitcomprising a non-therapeutic fluid reservoir for supplying correspondingdispensing nozzles with said fluid and a pumping unit for pumping fluidfrom the reservoir to said corresponding dispensing nozzles, saidpumping unit of said at least one fluid supply circuit being activatedonly when said arm is moved above said tray.
 11. The method according toclaim 10, characterized in that said arm (16) bearing a first set ofdispensing nozzles (18) and a second set of dispensing nozzles (19),said nozzles of each set being arranged to cover the entire dimension ofthe tray (15) in a second direction perpendicular to the firstdirection, droplets of at least a first fluid are dispensedsimultaneously by means of said first set of dispensing nozzles, anddroplets of at least a second fluid, distinct from the first fluid, aredispensed simultaneously by means of said second set of dispensingnozzles.
 12. The method according to claim 10, characterized in thatsaid arm (16) bearing a first set of dispensing nozzles (18) and asecond set of dispensing nozzles (19), said nozzles of each set beingarranged to cover the entire dimension of the tray (15) in a seconddirection perpendicular to the first direction, the following steps areperformed a) first distributing droplets of at least a first fluid byspraying by means of the first set of dispensing nozzles (18), b) thenat least one second fluid, distinct from the at least one first fluid tobe sprayed, is distributed by ejecting individual drops by means of thesecond set of dispensing nozzles (19).
 13. The method according to claim12, characterized in that steps a) and b) are performed in a single passof the mobile arm (16) over said tray (15), said nozzle assemblies beingarranged on said arm in such a way as to generate a time lag betweensteps a) and b).
 14. The method according to claim 13, characterized inthat the time lag between steps a) and b) is determined to guarantee theeffective treatment of the poultry by said at least one second fluid.15. The method according to claim 12, characterized in that step a) isperformed as said arm moves from a first edge to a second edge of saidtray (15), said second edge being opposite said first edge, on a forwardpath extending along said first direction and step b) is performed assaid arm moves from said second edge to said first edge on a return pathalong said first direction.